/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: 22652
 * Date: 2024-05-19
 * Time: 13:46
 */
public class wiggleMaxLength {
    public int wiggleMaxLength(int[] nums) {
        int n = nums.length;
        if (n < 2) return n;
        int ret = 0, left = 0;
        for (int i = 0; i < n - 1; i++) {
            int right = nums[i + 1] - nums[i];
            if (right == 0) continue;
            if (right * left < 0) {
                ret++;
            }
            left = right;
        }
        return ret + 1;
    }
}
